Radiation image processing device, radiation image processing method, and radiation image processing program

Abstract

A processor is configured to: acquire first to (n−1)th (n≥3) radiation images acquired by imaging a subject, which includes a first component consisting of a plurality of compositions and second to nth components each consisting of a single composition, with n−1 types of radiation having different energy distributions; derive a characteristic of the first component in at least a region of the subject in the first to (n−1)th radiation images; acquire a body thickness of the subject; derive thicknesses of the first to nth components by using the body thickness, the characteristic of the first component, and the first to (n−1)th radiation images; and derive first to nth component images in which the first to nth components are enhanced, respectively, based on the thicknesses of the first to nth components.

What is claimed is: 
     
         1 . A radiation image processing device comprising:
 at least one processor,   wherein the processor is configured to:
 acquire first to (n−1)th (n≥3) radiation images acquired by imaging a subject, which includes a first component consisting of a plurality of compositions and second to nth components each consisting of a single composition, with n−1 types of radiation having different energy distributions; 
 derive a characteristic of the first component in at least a region of the subject in the first to (n−1)th radiation images; 
 acquire a body thickness of the subject; 
 derive thicknesses of the first to nth components by using the body thickness, the characteristic of the first component, and the first to (n−1)th radiation images; and 
 derive first to nth component images in which the first to nth components are enhanced, respectively, based on the thicknesses of the first to nth components. 
   
     
     
         2 . The radiation image processing device according to  claim 1 ,
 wherein the processor is configured to acquire the body thickness by deriving the body thickness of the subject based on at least one of the first to (n−1)th radiation images.   
     
     
         3 . The radiation image processing device according to  claim 1 ,
 wherein the processor is configured to derive an attenuation coefficient of the first component as the characteristic of the first component.   
     
     
         4 . The radiation image processing device according to  claim 2 ,
 wherein the processor is configured to derive an attenuation coefficient of the first component as the characteristic of the first component.   
     
     
         5 . The radiation image processing device according to  claim 3 ,
 wherein the processor is configured to derive the attenuation coefficient of the first component as the characteristic of the first component based on information related to an attenuation coefficient of the radiation of each of the plurality of compositions included in the first component and a thickness of each of the plurality of compositions.   
     
     
         6 . The radiation image processing device according to  claim 4 ,
 wherein the processor is configured to derive the attenuation coefficient of the first component as the characteristic of the first component based on information related to an attenuation coefficient of the radiation of each of the plurality of compositions included in the first component and a thickness of each of the plurality of compositions.   
     
     
         7 . The radiation image processing device according to  claim 1 ,
 wherein the processor is configured to:
 acquire a first radiation image and a second radiation image that are acquired by imaging the subject with two types of radiation having different energy components; 
 derive the characteristic of the first component in at least a region of the subject in the first radiation image or the second radiation image; 
 derive the body thickness of the subject based on at least one of the first radiation image or the second radiation image; 
 derive thicknesses of the first component, a second component, and a third component of the subject by using the body thickness, the characteristic of the first component, the first radiation image, and the second radiation image; and 
 derive a first component image, a second component image, and a third component image in which the first component, the second component, and the third component are enhanced, respectively, based on the thicknesses of the first component, the second component, and the third component. 
   
     
     
         8 . The radiation image processing device according to  claim 2 ,
 wherein the processor is configured to:
 acquire a first radiation image and a second radiation image that are acquired by imaging the subject with two types of radiation having different energy components; 
 derive the characteristic of the first component in at least a region of the subject in the first radiation image or the second radiation image; 
 derive the body thickness of the subject based on at least one of the first radiation image or the second radiation image; 
 derive thicknesses of the first component, a second component, and a third component of the subject by using the body thickness, the characteristic of the first component, the first radiation image, and the second radiation image; and 
 derive a first component image, a second component image, and a third component image in which the first component, the second component, and the third component are enhanced, respectively, based on the thicknesses of the first component, the second component, and the third component. 
   
     
     
         9 . The radiation image processing device according to  claim 3 ,
 wherein the processor is configured to:
 acquire a first radiation image and a second radiation image that are acquired by imaging the subject with two types of radiation having different energy components; 
 derive the characteristic of the first component in at least a region of the subject in the first radiation image or the second radiation image; 
 derive the body thickness of the subject based on at least one of the first radiation image or the second radiation image; 
 derive thicknesses of the first component, a second component, and a third component of the subject by using the body thickness, the characteristic of the first component, the first radiation image, and the second radiation image; and 
 derive a first component image, a second component image, and a third component image in which the first component, the second component, and the third component are enhanced, respectively, based on the thicknesses of the first component, the second component, and the third component. 
   
     
     
         10 . The radiation image processing device according to  claim 4 ,
 wherein the processor is configured to:
 acquire a first radiation image and a second radiation image that are acquired by imaging the subject with two types of radiation having different energy components; 
 derive the characteristic of the first component in at least a region of the subject in the first radiation image or the second radiation image; 
 derive the body thickness of the subject based on at least one of the first radiation image or the second radiation image; 
 derive thicknesses of the first component, a second component, and a third component of the subject by using the body thickness, the characteristic of the first component, the first radiation image, and the second radiation image; and 
 derive a first component image, a second component image, and a third component image in which the first component, the second component, and the third component are enhanced, respectively, based on the thicknesses of the first component, the second component, and the third component. 
   
     
     
         11 . The radiation image processing device according to  claim 5 ,
 wherein the processor is configured to:
 acquire a first radiation image and a second radiation image that are acquired by imaging the subject with two types of radiation having different energy components; 
 derive the characteristic of the first component in at least a region of the subject in the first radiation image or the second radiation image; 
 derive the body thickness of the subject based on at least one of the first radiation image or the second radiation image; 
 derive thicknesses of the first component, a second component, and a third component of the subject by using the body thickness, the characteristic of the first component, the first radiation image, and the second radiation image; and 
 derive a first component image, a second component image, and a third component image in which the first component, the second component, and the third component are enhanced, respectively, based on the thicknesses of the first component, the second component, and the third component. 
   
     
     
         12 . The radiation image processing device according to  claim 6 ,
 wherein the processor is configured to:
 acquire a first radiation image and a second radiation image that are acquired by imaging the subject with two types of radiation having different energy components; 
 derive the characteristic of the first component in at least a region of the subject in the first radiation image or the second radiation image; 
 derive the body thickness of the subject based on at least one of the first radiation image or the second radiation image; 
 derive thicknesses of the first component, a second component, and a third component of the subject by using the body thickness, the characteristic of the first component, the first radiation image, and the second radiation image; and 
 derive a first component image, a second component image, and a third component image in which the first component, the second component, and the third component are enhanced, respectively, based on the thicknesses of the first component, the second component, and the third component. 
   
     
     
         13 . The radiation image processing device according to  claim 1 ,
 wherein the first component, the second component, and the third component are a soft part and a bone part of the subject and an artificial object in the subject, respectively.   
     
     
         14 . The radiation image processing device according to  claim 13 ,
 wherein the compositions of the first component are fat and muscle.   
     
     
         15 . A radiation image processing method executed by a computer, the radiation image processing method comprising:
 acquiring first to (n−1)th (n≥3) radiation images acquired by imaging a subject, which includes a first component consisting of a plurality of compositions and second to nth components each consisting of a single composition, with n−1 types of radiation having different energy distributions;   deriving a characteristic of the first component in at least a region of the subject in the first to (n−1)th radiation images;   acquiring a body thickness of the subject;   deriving thicknesses of the first to nth components by using the body thickness, the characteristic of the first component, and the first to (n−1)th radiation images; and   deriving first to nth component images in which the first to nth components are enhanced, respectively, based on the thicknesses of the first to nth components.   
     
     
         16 . Anon-transitory computer-readable storage medium that stores a radiation image processing program causing a computer to execute:
 a procedure of acquiring first to (n−1)th (n≥3) radiation images acquired by imaging a subject, which includes a first component consisting of a plurality of compositions and second to nth components each consisting of a single composition, with n−1 types of radiation having different energy distributions;   a procedure of deriving a characteristic of the first component in at least a region of the subject in the first to (n−1)th radiation images;   a procedure of acquiring a body thickness of the subject;   a procedure of deriving thicknesses of the first to nth components by using the body thickness, the characteristic of the first component, and the first to (n−1)th radiation images; and   a procedure of deriving first to nth component images in which the first to nth components are enhanced, respectively, based on the thicknesses of the first to nth components.